He trudged slowly, a walking boot protecting his surgically repaired left ankle better than his offensive line protected him last season, a season Eli Manning can’t wait to scramble away from … a season that left questions about whether you can’t spell D-E-C-L-I-N-E without an E, an L and an I.

Against the backdrop of his first surgery, a new offensive coordinator, a new offense and so many new teammates to learn to trust, the vultures of uncertainty and concern circle around the franchise quarterback of the New York Football Giants.

The word from Eli Manning: There is no D-E-C-L-I-N-E in Eli.

Manning was asked if he thinks his best football is still ahead of him, and what he would tell Giants fans who have been reading the word decline next to his name.

“I think I got great football ahead of me,” he said. “I’m excited about the new offense that we have, and the way that I can play within this offense. A lot of it seems to fit my strengths, so I’m looking forward to working, learning and getting around our teammates and getting back to where we’re winning games and making the playoffs and giving ourself an opportunity to winning another championship.”

“So you’re not in decline?”

Manning, wearing a walking boot on his surgically repaired ankle, answers a question as he walks away from Tuesday’s news conference.Photo: Jeff Zelevansky

“No, I’m not in decline,” Manning told The Post.

He is 33-years-old somehow, coming off a nightmare 27-interception season.

And the ankle surgery.

And the Giants still believe in him just the same.

“I think that’s kind of crazy,” Giants co-owner John Mara said. “Let’s give him a chance to get back on the field. Certainly he didn’t have his best season last year, but he had a lot of company there, we didn’t give him a lot of help, and hopefully we’ll be able to do that for him this year.

“But we still believe we can win championships with him.”

New offensive coordinator Ben McAdoo, the replacement for Kevin Gilbride, brings new West Coast ideas to stimulate Manning and cure what the powers-that-be determined was a stagnant offense.

“You almost feel like this an opportunity to reinvent yourself, and to come back and change what occurred last year, some of the difficulties, and bounce back and have a clean slate to prove yourself again and get back to play at a high level,” Manning said.

The sight of Manning in a walking boot is a sobering one for Big Blue Nation given that Manning has yet to miss a game since becoming the starter after the ninth game of the 2004 season. But surgery was prudent.

“It’ll give me plenty of time to heal and be 100 percent healthy for the season,” Manning said.

A few minutes later: “I think I’d be safe to say, yeah, I should be 100 percent by training camp.”

Manning will know this offense like the back of his hand by the start of the season.

“I’m excited,” Manning said. “It does bring a sense of urgency to the offseason this time of year. In some years you come in kind of knowing an offense and you’re looking to get better. Now, you got to learn new things, different techniques, different fundamentals … a lot going on, the mind’s swimming a little bit right now.

“But it’s an exciting time. Look forward to conquering it.”

He’ll be helping his teammates, new and old, conquer it as well.

“This is my second offense I’ve had to learn. … It’s a little different than 10 years ago when I was a rookie in the NFL trying to learn a system now,” Manning said. “I have an understanding of the game of football better. In a lot of cases, it’s the same things said a little differently. I’ll make sure I’m ready, I’ll have time to learn the offense and practice it, and be on the same page as everybody.”

Especially Victor Cruz.

“I think it’s going to be even easier for us to connect, easier for us to be on the same page,” Cruz said. “A lot of my routes were determined against what type of coverage they were in, and they would dictate my route. As far as this offense is concerned, it’s a lot more your route is your route and you can dictate that off your coverage and you know what you have, and Eli can find you within those different holes. So now it’s a lot less dependent on what my body language is and Eli reading that, it’s more so just him reading the coverage, and finding me in those open holes.”

By all accounts, McAdoo is an impressive mind.

“I think it’ll be similar to what they did in Green Bay,” Manning said. “I’ve never been in a West Coast offense, so I don’t know if this is exactly West Coast or a form of it or not anything at all like it. Every offense had its own little style, it’s own uniqueness that makes it work.”

A cortisone shot a few weeks prior to the surgery, which was performed, two weeks ago blocked some of the discomfort he had felt earlier.

“We felt when that wore off that maybe that pain would come back and I’d be in kind of the same boat that I was in earlier,” Manning said.

Manning cleared up suspicions that hooping it up at Duke caused his problem.